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Mail Archives: djgpp/2001/11/25/12:28:06

Date: Sun, 25 Nov 2001 19:23:29 +0200
From: "Eli Zaretskii" <eliz AT is DOT elta DOT co DOT il>
Sender: halo1 AT zahav DOT net DOT il
To: Martin Steuer <martinSteuer AT gmx DOT de>
Message-Id: <2561-Sun25Nov2001192329+0200-eliz@is.elta.co.il>
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CC: djgpp AT delorie DOT com
In-reply-to: <5.0.2.1.2.20011125104031.009d1910@pop.gmx.net> (message from
Martin Steuer on Sun, 25 Nov 2001 11:34:00 +0100)
Subject: Re: Problems with gdb???
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> Date: Sun, 25 Nov 2001 11:34:00 +0100
> From: Martin Steuer <martinSteuer AT gmx DOT de>
> 
> While composing this message i found a problem within the wrapper's code 
> and fixed this but now the situation gets even more worse: Under bare DOS 
> the program crashes without being debugged (SIGSEGV) in a call to getch() 
> at getch()+153 (this is after the installation of the IRQ Handler) which i 
> use to loop a sound until one presses a key.
> DS to GS are all zero and the stack selector is invalid.
> At least i'm now sure that the problem lies in my code...

Well, one thing I see in the wrapper is that it doesn't disable
interrupts in all cases where it modifies SS and ESP.  If an
interrupt hits when SS and ESP are not in sync, you are toast.

getch() issues a real-mode interrupt, so your problem might have
something to do with the mode switch.

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